Development of Model for Grain Growth in UO 2 Fuel

Abstract

A new recently proposed mechanism of the lenticular grain face bubble migration which controls the bubble mobility and determines the drag force exerted on the grain boundary, is further developed in application to the peripheral (edge and corner) intergranular bubbles. It is shown that contribution of the peripheral bubbles to the retarding effect can be significant, especially under irradiation conditions with high fission rates in UO2 fuel. In addition, simultaneous consideration of intergranular bubbles and pores evolution allows further improvement of the model predictions for grain growth under irradiation conditions. The improved model was implemented in the integral code MFPR, which is designed for modelling of fission product release from irradiated UO2 fuel, and validated against various tests under irradiation and annealing conditions with various types (dense and porous) fuel pellets.

Citation

Antropov, D.S. and Veshchunov, M.S. (2008), "Development of Model for Grain Growth in UO 2 Fuel", Multidiscipline Modeling in Materials and Structures, Vol. 4 No. 2, pp. 125-140. https://doi.org/10.1163/157361108784050068